The present invention relates to mapping of a network topology comprising a plurality of elements with one or more interconnections between the plurality of elements, and in particular to the provision of a graphical representation of the network topology.
A network generally represents an arrangement of nodes and connecting branches. In a computer network, two or more computers are connected with one another for the purpose of communicating data electronically. The schematic arrangement of the links and nodes of a network is normally represented in a network topology (or network structure) describing the topographical layout of the network.
FIG. 1 shows a typical mapping or graphical representation of a network topology consisting of a plurality of elements S1 to S6, A and B. The term xe2x80x9celementxe2x80x9d as used herein may represent one or more individual elements, groups of elements, one or more subnets, or the like. In the example of FIG. 1, the elements A and B shall represent specific networking devices A and B for connecting the elements S1 to S6. Each networking device might represent any kind of element or network connecting device such as a direct physical connection, a connection line, a router, or the like, as known in the art. If additional geographical data such as coordinates is available for the individual nodes in the network, a network map can be derived by scaling the real dimensions in the representation of FIG. 1.
In case that the geographical information is either not available or not relevant, the visualized representation of the network as shown in FIG. 1 might be inappropriate because the positions of the displayed network elements cannot reflect the real geometry of the network. However, this approach is widely used and the coordinates are often calculated by layout algorithms that optimize the network map in a static way, such as avoidance of long edges between nodes and avoidance of overlapping elements. Those layout algorithms may also cause unexpected results since there are no constraints that may limit reorganizations resulting from changes such as element additions or deletions.
A data record representing a network topology generally comprises data representing (the identity of) each element and data representing interconnection(s) between the individual elements. The elements and interconnections in computer networks, e.g. of an Internet protocol type, are usually discovered by queries of a network management system to the individual elements and devices within the network. A router, for example, holds internal configuration data about the connected subnets or other elements that can be retrieved via the network management protocols. The network topology can thus be discovered and stored into data structures comprising data records with at least the minimum information as discussed above. The physical network topology usually cannot be discovered in that way and by those means.
FIG. 2 shows a data record 10, comprising the essential data about the network topology, which is provided to an information processing unit (IPU) 20 which processes and maps the data record 10 to a graphical representation 30 of the network topology as depicted e.g. in FIG. 1.
Another graphical representation 30 of the network topology as known in the art is in form of a connection tree as depicted in FIG. 3. Starting from element A, all elements connected to element A are represented as xe2x80x9csub-elementsxe2x80x9d S1, S2, S3, and S4. Element S3 again provides as xe2x80x9csub-elementsxe2x80x9d connections to elements A and B, and so on. This tree representation leads to a clear structure when the network to be represented has a clear hierarchical tree structure with a plurality of branches. However, the tree structure leads to an unclear repetition of xe2x80x9csub-elementsxe2x80x9d in case that the network structure comprises connection loops or parallel connections.
It is an object of the present invention to provide an improved mapping of a network topology.
According to the invention, the mapping of a network topology or structure, comprising a plurality of elements with one or more interconnections between the plurality of elements, is accomplished by representing the plurality of elements in a first matrix dimension, and representing the one or more interconnections in a second matrix dimension. The mapping is preferably used for providing a graphical representation of the network topology.
Compared to the map layout without geographical information as shown in FIG. 1, the matrix based network graphical representation according to the invention offers several advantages such as: No misleading positions of elements introduced by layout algorithms without any relation to the real network geometry, alphanumeric sorting may be applied, adding or deleting of elements results e.g. in inserting or removing lines without major restructuring as required for maps. Converting network topology data (with or without geographical information) according to the invention further avoids the problems introduced by free map style layouts as used by current network management systems.
Within computer aided network management systems, the described network graphical representation requires less computational effort. It also offers higher flexibility as expanding subnets to segments or changing drawing styles such as highlighting of defective elements or changing a dot shape at a point of intersection between the first and second matrix dimension depending on the type of network interface.
In a preferred embodiment, a group of elements can be represented in a third matrix dimension.
In another preferred embodiment, instead of representing a connecting device for connecting groups of elements in the first matrix dimension, the connecting device can be ,represented in the second matrix dimension. This allows to better distinguishing between separate groups of elements.
In one embodiment, the plurality of elements is represented by parallel lines in the first matrix dimension, and/or the one or more interconnections by parallel lines are represented in the second matrix dimension.
A connection between two elements is preferably represented by dots at the points of intersection between the representation of the interconnection between two elements in the second matrix dimension and the representations of the elements in the first matrix dimension.
In a further preferred embodiment, the first matrix dimension is substantially perpendicular to the second matrix dimension.